Add requirements.txt to setup.py package_data.

 * Fix error on PyPI download due to requirements.txt missing; this file is
   parsed for package requirements upon installation.
Merge branch 'release/1.1.4'
Merge branch 'master' into develop
Call the requirement.txt file from the current directory, not maintainer dir.
Update author contact info and package urls.
Remove unused function get_current_dir() from setup.py.
Merge branch 'release/1.1.5'
Merge branch 'master' into develop